Everyone can get a library card, as long as you have a valid identification and are at least 16 years old.
You have to agree to abide by the loan regulations, in order to borrow from the library. If you have borrowed a book, you are then responsible for the book. If one of your books is overdue, or if you don't return it at all, you may get an overdue fine and eventually an invoice. Read more here about overdue fines and invoices.
Go to the loan regulations.